Light-emitting module

Abstract

This light-emitting module comprises: a support substrate having a plurality of placement surfaces arranged side by side in a first direction; a plurality of light-emitting devices, the corresponding light-emitting devices being disposed on the respective placement surfaces, and each including a semiconductor laser element, a first mirror member, a cover, and a second mirror member; a plurality of third mirror members; and a light condensing lens. The first mirror member changes the traveling direction of laser light emitted from the semiconductor laser element, the cover transmits the laser light having the changed traveling direction, the second mirror member further changes the traveling direction of the laser light transmitted through the cover to a second direction, and each third mirror member changes the traveling direction of the laser light from the second direction to the first direction. The light condensing lens couples a plurality of laser light beams to optical fibers.

Description

Light-emitting module

[0001] The present disclosure relates to a light emitting module.

[0002] In recent years, with the increasing power output of semiconductor laser elements, a technology is being developed in which semiconductor laser elements are used not as excitation light sources but as light sources of laser light for directly irradiating and processing materials. This technology is called direct diode laser (DDL) technology.

[0003] The DDL technology uses a light-emitting module including multiple semiconductor laser elements. The light-emitting module combines multiple laser beams obtained by emitting laser beams from the multiple semiconductor laser elements to emit high-power laser beams. When the propagation directions of the multiple laser beams are aligned in the same direction as designed, the multiple laser beams can be effectively combined. Patent Document 1 discloses an example of an optical component that can reduce the deviation between the propagation direction of laser beams emitted from the semiconductor laser elements and the design propagation direction.

[0004] International Publication No. 2016 / 051836

[0005] A light emitting module including a plurality of light emitting devices capable of reducing the deviation between the traveling direction of laser light emitted from a semiconductor laser element and the designed traveling direction.

[0006] In one embodiment, the light emitting module of the present disclosure includes: a support base having a plurality of mounting surfaces aligned in a first direction; a plurality of light emitting devices, each of which has a corresponding light emitting device disposed on each of the plurality of mounting surfaces, the plurality of light emitting devices comprising: a substrate having a mounting surface; a semiconductor laser element supported by the mounting surface; a first mirror member supported by the mounting surface; a facing surface facing the mounting surface of the substrate; and a top surface located opposite the facing surface, the plurality of light emitting devices comprising: a cover positioned above the semiconductor laser element and the first mirror member; and a second mirror member supported by the top surface of the cover; a plurality of third mirror members; and a condensing lens, wherein the first mirror member has a first reflective surface that is inclined with respect to the mounting surface and faces obliquely upward; the semiconductor laser element is positioned above at least a portion of the first reflecting surface, and is arranged to emit laser light toward the first reflecting surface; the first reflecting surface reflects the laser light to change the direction of travel of the laser light in a direction away from the mounting surface of the board; the cover transmits the laser light reflected by the first reflecting surface; the second reflecting surface reflects the laser light reflected by the first reflecting surface to further change the direction of travel of the laser light to a second direction intersecting the first direction; each of the plurality of third mirror members has a third reflecting surface, and the third reflecting surface reflects the laser light traveling in the second direction to change the direction of travel of the laser light to the first direction; and the focusing lens couples the plurality of laser light beams obtained by the laser light emitted from each of the plurality of light-emitting devices being reflected by the third reflecting surface into an optical fiber.

[0007] According to the embodiments of the present disclosure, it is possible to realize a light emitting module including a plurality of light emitting devices that can reduce the deviation between the traveling direction of laser light emitted from a semiconductor laser element and the designed traveling direction.

[0008] FIG. 1A is a top view schematically illustrating a configuration of a light-emitting module according to an exemplary embodiment of the present disclosure. FIG. 1B is a side view schematically illustrating a configuration of a light-emitting module according to an exemplary embodiment of the present disclosure. FIG. 1C is another side view schematically illustrating a configuration of a light-emitting module according to an exemplary embodiment of the present disclosure. FIG. 1D is a top view schematically illustrating a configuration of a modified light-emitting module according to an embodiment of the present disclosure. FIG. 2A is a perspective view schematically illustrating a configuration of a light-emitting device according to an exemplary embodiment of the present disclosure. FIG. 2B is an exploded perspective view of the light-emitting device shown in FIG. 2A. FIG. 2C is another exploded perspective view of the light-emitting device shown in FIG. 2A. FIG. 2D is a perspective view of a frame included in the light-emitting device shown in FIG. 2C, viewed from below. FIG. 2E is a top view of a configuration in which a second mirror member and a cover are omitted from the light-emitting device shown in FIG. 2A. FIG. 2F is a cross-sectional view parallel to the YZ plane of the light-emitting device shown in FIG. 2A. FIG. 3 is a diagram schematically illustrating a configuration of a DDL device according to an exemplary embodiment of the present disclosure. FIG. 4A is an exploded perspective view of a laser light source. FIG. 4B is a cross-sectional view of the laser light source parallel to the YZ plane.

[0009] Hereinafter, a light emitting device and a light emitting module including a plurality of light emitting devices according to embodiments of the present disclosure will be described with reference to the drawings. Parts that appear in multiple drawings with the same reference numerals indicate the same or equivalent parts.

[0010] Furthermore, the embodiments described below are examples to embody the technical idea of ​​the present invention, and do not limit the present invention. Furthermore, the size, material, shape, relative arrangement, etc. of components are intended to be illustrative and not to limit the scope of the present invention. The size and positional relationship of components shown in each drawing may be exaggerated to facilitate understanding.

[0011] In this specification and claims, polygons such as triangles and quadrilaterals are referred to as polygons, including shapes in which the corners of the polygon have been rounded, chamfered, corner-cut, or rounded. Shapes in which processing has been applied not only to the corners (edges of the sides) but also to the middle of the sides are also referred to as polygons. In other words, shapes in which partial processing has been applied while retaining the polygonal base are included in the interpretation of "polygon" described in this specification and claims.

[0012] (Embodiment) [Light Emitting Module] First, with reference to FIGS. 1A to 1C, an example configuration of a light emitting module according to an embodiment of the present disclosure will be described. FIG. 1A is a top view schematically illustrating the configuration of a light emitting module according to an exemplary embodiment of the present disclosure. FIG. 1B is a side view schematically illustrating the configuration of a light emitting module according to an exemplary embodiment of the present disclosure. FIG. 1C is another side view schematically illustrating the configuration of a light emitting module according to an exemplary embodiment of the present disclosure. In these figures, for reference, mutually orthogonal X-, Y-, and Z-axes are schematically illustrated. The direction of the X-axis arrow is referred to as the +X direction, and the opposite direction is referred to as the −X direction. When there is no distinction between the ±X directions, they are simply referred to as the X direction. The same applies to the Y and Z directions. In this specification, for ease of understanding, the +Y direction will be referred to as "upward" and the −Y direction will be referred to as "downward." This does not limit the orientation of the light emitting module during use, and the orientation of the light emitting module is arbitrary.

[0013] 1A to 1C includes a support base 60, a condenser lens 70, an optical fiber 80, a support member 82 that supports the optical fiber 80, a plurality of slow-axis collimating lenses 92, a plurality of mirror members 94, and a plurality of light-emitting devices 100. Each mirror member 94 has a reflective surface 94s.

[0014] As shown in FIG. 1B , the support base 60 is disposed on a reference plane Ref parallel to the XZ plane. The reference plane Ref is a reference plane for the height of the light-emitting module 200. As shown in FIG. 1A , the support base 60 includes a first portion 60-1 that supports a plurality of light-emitting devices 100. The support base 60 further includes a plurality of second portions 60-2 supported by the first portion 60-1. Each second portion 60-2 supports a corresponding slow-axis collimating lens 92 and mirror member 94. The support base 60 further includes a third portion 60-3 connected to the first portion 60-1. The third portion 60-3 supports a condenser lens 70 and an optical fiber 80.

[0015] The first portion 60-1 has a plurality of first placement surfaces 60s1 aligned in the X direction. A corresponding second portion 60-2 is disposed on each first placement surface 60s1. Each second portion 60-2 has a second placement surface 60s2. The third portion 60-3 has a third placement surface 60s3.

[0016] As shown in FIG. 1B , the heights of the multiple first mounting surfaces 60s1 decrease stepwise along the +X direction. The same applies to the heights of the multiple second mounting surfaces 60s2. As shown in FIG. 1A , a corresponding light-emitting device 100 is disposed on each first mounting surface 60s1. A corresponding slow-axis collimating lens 92 and mirror member 94 are disposed on each second mounting surface 60s2. If the slow-axis collimating lens 92 and / or mirror member 94 have a sufficiently large dimension in the Y direction, the slow-axis collimating lens 92 and / or mirror member 94 may be disposed on the first mounting surface 60s1 without the second portion 60-2. On the third mounting surface 60s3, a condenser lens 70 is disposed, and an optical fiber 80 is disposed via a support member 82.

[0017] 1B , the height of the third mounting surface 60s3 is greater than the minimum height of the plurality of first mounting surfaces 60s1 and less than the maximum height. The height of the third mounting surface 60s3 is also less than the minimum height of the plurality of second mounting surfaces 60s2. Depending on the dimension of the condenser lens 70 in the Y direction, the height of the third mounting surface 60s3 may be equal to or less than the minimum height of the plurality of first mounting surfaces 60s1. Alternatively, the height of the third mounting surface 60s3 may be equal to or greater than the maximum height of the plurality of first mounting surfaces 60s1.

[0018] 1A to 1C, the number of light-emitting devices 100 is four, and the number of first mounting surfaces 60s1 is four, but these numbers are not limited to these. The number of light-emitting devices 100 may be two, three, five or more. The more the number of light-emitting devices 100 increases, the higher the output of laser light can be obtained. The number of first mounting surfaces 60s1 may be two, three, five or more, or may be equal to or greater than the number of light-emitting devices 100.

[0019] The support base 60 may be formed of, for example, a ceramic selected from the group consisting of AlN, SiN, SiC, and alumina. Alternatively, the support base 60 may be formed of, for example, at least one metal material selected from the group consisting of Cu, Al, and Ag. The support base 60 may be formed of, for example, a metal matrix composite material in which diamond particles are dispersed in at least one metal material selected from the group consisting of Cu, Al, and Ag. The support base 60 may be formed integrally or may be an assembly of multiple parts. The multiple parts may be formed from the same material or different materials. For example, the first portion 60-1, the multiple second portions 60-2, and the third portion 60-3 may be formed integrally or independently. Alternatively, the first portion 60-1 and the third portion 60-3 may be integrally formed, and the plurality of second portions 60-2 may be formed independently of the first portion 60-1 and the third portion 60-3.

[0020] The support base 60 is preferably made of a metal material selected from the group consisting of Cu, Al, and Ag, and is made of a single member. Metal materials have better heat dissipation properties than ceramics, and are soft and therefore easy to process.

[0021] The support base 60 functions as a support base on which the plurality of light-emitting devices 100 are placed. The support base 60 can also function as a heat sink that transfers heat generated from the plurality of light-emitting devices 100 to the outside to reduce excessive temperature rise of the light-emitting devices 100. In this case, one or more flow paths for liquid cooling may be provided inside the support base 60. The liquid used for liquid cooling may be, for example, water. Furthermore, a fin structure for air cooling may be provided on the surface of the support base 60. Alternatively, when the support base 60 is placed on a separately prepared heat sink, the support base 60 can also function as a heat spreader that transfers heat generated from the plurality of light-emitting devices 100 to the heat sink.

[0022] As shown in FIGS. 1A and 1C, each light-emitting device 100 emits laser light L in the +Z direction. As shown in FIG. 1A, each slow-axis collimating lens 92 collimates, in the XZ plane, the laser light emitted from the corresponding light-emitting device 100 and traveling in the +Z direction. As shown in FIGS. 1A and 1B, the reflecting surface 94s of each mirror member 94 reflects the collimated laser light L emitted from the corresponding light-emitting device 100 and changes the traveling direction of the laser light L toward the condenser lens 70 in the +X direction. The laser light L emitted from each light-emitting device 100 is represented by a thick line with three arrows in the example shown in FIG. 1A, and by a thick line with one arrow in the examples shown in FIGS. 1B and 1C. In the example shown in FIG. 1A, the laser light L is represented by a thick line with three arrows to emphasize that the laser light L has a divergence.

[0023] The condenser lens 70 has a fast-axis condenser lens 70a and a slow-axis condenser lens 70b. The fast-axis condenser lens 70a may be, for example, a cylindrical lens having a uniform cross-sectional shape in the Z direction, and the slow-axis condenser lens 70b may be, for example, a cylindrical lens having a uniform cross-sectional shape in the Y direction. The optical axes of the fast-axis condenser lens 70a and the slow-axis condenser lens 70b are parallel to the X direction. The condenser lens 70 may be formed from at least one light-transmitting material selected from the group consisting of, for example, glass, silicon, quartz, synthetic quartz, sapphire, transparent ceramics, silicone resin, and plastic.

[0024] The fast axis focusing lens 70a is disposed so that its focal point substantially coincides with the light-incident end 80a of the optical fiber 80. Similarly, the slow axis focusing lens 70b is disposed so that its focal point substantially coincides with the light-incident end 80a of the optical fiber 80. The focal length of the fast axis focusing lens 70a is longer than the focal length of the slow axis focusing lens 70b. As shown in FIG. 1B , the fast axis focusing lens 70a converges, in the XY plane, the multiple laser beams L obtained by emitting the laser beams L from each of the multiple light-emitting devices 100, onto the light-incident end 80a of the optical fiber 80. As shown in FIG. 1A , the slow axis focusing lens 70b converges, in the XZ plane, the laser beams L having a divergence and emitted from each of the multiple light-emitting devices 100, onto the light-incident end 80a.

[0025] As described above, the laser light L emitted in the +Z direction from each of the plurality of light-emitting devices 100 is reflected in the +X direction by the corresponding reflecting surface 94s. The plurality of laser light beams L thus obtained can be combined by the condenser lens 70 and made incident on the optical fiber 80.

[0026] As a result, the light-emitting module 200 emits combined light obtained by combining multiple laser beams L from the light-emitting end 80b of the optical fiber 80. The output of the combined light is roughly equal to the value obtained by multiplying the output of the laser beams L emitted from each light-emitting device 100 by the number of light-emitting devices 100. Therefore, by increasing the number of light-emitting devices 100, the output of the combined light can be increased.

[0027] Next, a modified example of the light emitting module 200 according to the embodiment of the present disclosure will be described with reference to Fig. 1D. Fig. 1D is a top view schematically illustrating the configuration of the modified example of the light emitting module according to the embodiment of the present disclosure. The light emitting module 210 shown in Fig. 1D differs from the light emitting module 200 shown in Figs. 1A to 1C in the following three points.

[0028] The first difference is that the light-emitting module 210 includes a support base 62 instead of the support base 60. The shape of the support base 62 is different from the shape of the support base 60. The second difference is that the light-emitting module 210 further includes a plurality of light-emitting devices 100-2, a plurality of slow-axis collimating lenses 92b, and a plurality of mirror members 94b in addition to the plurality of light-emitting devices 100-1, a plurality of slow-axis collimating lenses 92a, and a plurality of mirror members 94a. Each mirror member 94a has a reflective surface 94as, and each mirror member 94b has a reflective surface 94bs. The third difference is that the light-emitting module 210 further includes a mirror member 94c, a half-wave plate 96, and a polarizing beam splitter 98. The mirror member 94c has a reflective surface 94cs.

[0029] The support base 62 includes a first portion 62-1 that supports the plurality of light-emitting devices 100-1 and the plurality of light-emitting devices 100-2. The support base 62 further includes a plurality of second portions 62-2 supported by the first portion 62-1. Each second portion 62-2 supports a corresponding slow-axis collimating lens 92a, slow-axis collimating lens 92b, mirror member 94a, and mirror member 94b. The support base 62 further includes a third portion 62-3 connected to the first portion 62-1. The third portion 62-3 supports the condenser lens 70, the optical fiber 80, the mirror member 94c, the half-wave plate 96, and the polarizing beam splitter 98.

[0030] The first portion 62-1 has a plurality of first placement surfaces 60s1 aligned in the X direction. A corresponding second portion 62-2 is disposed on each first placement surface 60s1. Each second portion 62-2 has a second placement surface 60s2. The third portion 62-3 has a third placement surface 60s3.

[0031] The light-emitting device 100-2, slow-axis collimating lens 92a, and mirror member 94a have the same structures as the light-emitting device 100, slow-axis collimating lens 92, and mirror member 94 shown in FIG. 1A, respectively. The same is true for the light-emitting device 100-2, slow-axis collimating lens 92b, and mirror member 94b. The light-emitting device 100-1, slow-axis collimating lens 92a, and mirror member 94a are arranged in this order along the +Z direction, and the light-emitting device 100-2, slow-axis collimating lens 92b, and mirror member 94b are arranged in this order along the -Z direction. The arrangements of the light-emitting devices 100-1 and 100-2 are inverted relative to each other in the Z direction. The same is true for the arrangements of the slow-axis collimating lens 92a and slow-axis collimating lens 92b, and the arrangements of the mirror member 94a and mirror member 94b.

[0032] Each light-emitting device 100-1 and each light-emitting device 100-2 are disposed on a corresponding first mounting surface 60s1. Each light-emitting device 100-1 emits laser light La in the +Z direction, and each light-emitting device 100-2 emits laser light Lb in the -Z direction. The polarization directions of the laser light La and Lb are parallel to the X direction. Each slow-axis collimating lens 92a, each slow-axis collimating lens 92b, each mirror member 94a, and each mirror member 94b are disposed on a corresponding second mounting surface 60s2. Each slow-axis collimating lens 92a collimates, in the XZ plane, the laser light La emitted in the +Z direction from the corresponding light-emitting device 100-1. Each slow-axis collimating lens 92b collimates, in the XZ plane, the laser light Lb emitted in the -Z direction from the corresponding light-emitting device 100-2. The reflecting surface 94as of each mirror member 94a reflects the collimated laser beam La and changes the traveling direction of the laser beam La to the +X direction. The reflecting surface 94bs of each mirror member 94b reflects the collimated laser beam Lb and changes the traveling direction of the laser beam Lb to the +X direction.

[0033] The mirror member 94c, the half-wave plate 96, and the polarizing beam splitter 98 are disposed on the third mounting surface 60s3. The reflecting surface 94cs of the mirror member 94c reflects the laser light Lb traveling in the +X direction, changing the traveling direction of the laser light Lb to the −Z direction. The half-wave plate 96 changes the polarization direction of the laser light Lb traveling in the −Z direction from the X direction to the Y direction. The polarizing beam splitter 98 transmits the laser light La traveling in the +X direction and polarized in the Z direction, and reflects the laser light Lb traveling in the −Z direction and polarized in the Y direction. The laser light La transmitted through the polarizing beam splitter 98 is converged by the condenser lens 70 onto the light incident end 80a of the optical fiber 80. Similarly, the laser light Lb reflected by the polarizing beam splitter 98 is converged by the condenser lens 70 onto the light incident end 80a of the optical fiber 80.

[0034] As a result, the light-emitting module 210 emits combined light obtained by combining the multiple laser beams La and the multiple laser beams Lb from the light-emitting end 80b of the optical fiber 80. In the light-emitting module 210 illustrated in Fig. 1D, the total number of light-emitting devices 100-1 and 100-2 is twice the number of light-emitting devices 100, as compared to the light-emitting module 200 illustrated in Fig. 1A. Therefore, the output of the combined light can be further increased.

[0035] In light-emitting module 200, when the propagation directions of the plurality of laser beams L are aligned in the +X direction as designed, the plurality of laser beams L can be effectively combined by condenser lens 70 and made incident on optical fiber 80. The same applies to the case in light-emitting module 210 when the propagation directions of the plurality of laser beams La and the plurality of laser beams Lb are aligned in the +X direction as designed.

[0036] In the light-emitting module 200 according to the present embodiment, a corresponding light-emitting device 100 is disposed on each of a plurality of first mounting surfaces 60s1 that are at different heights from one another, but the present invention is not limited to such a configuration. Alternatively, a plurality of light-emitting devices 100 may be employed in a more general spatially coupled light-emitting module.

[0037] [Light-emitting device] Hereinafter, a configuration example of a light-emitting device according to an embodiment of the present disclosure will be described with reference to Figures 2A to 2F. The light-emitting device according to the embodiment of the present disclosure makes it possible to reduce the deviation between the traveling direction of laser light L and the designed traveling direction. In this specification, when the term "traveling direction" is simply used, such as the "traveling direction of laser light," the "traveling direction" refers to the actual traveling direction.

[0038] FIG. 2A is a perspective view schematically illustrating the configuration of a light-emitting device according to an exemplary embodiment of the present disclosure. FIG. 2B is an exploded perspective view of the light-emitting device shown in FIG. 2A. The light-emitting device 100 shown in FIG. 2B includes a substrate 10, a laser light source 20, a first mirror member 30a, a second mirror member 30b, a frame 40, multiple wires 40w, and a cover 50. The substrate 10 has a mounting surface 10us. The first mirror member 30a has a first reflecting surface 30as, and the second mirror member 30b has a second reflecting surface 30bs. The laser light source 20 is a chip-on-submount type semiconductor laser light source having a semiconductor laser element 22. The light-emitting device 100 may further include a protection element such as a Zener diode and / or a temperature measurement element for measuring the internal temperature such as a thermistor. FIG. 2C is another exploded perspective view of the light-emitting device 100 shown in FIG. 2A. The multiple wires 40w shown in FIG. 2B are omitted in FIG. 2C. Fig. 2D is a perspective view of the frame body 40 included in the light emitting device 100 shown in Fig. 2C, viewed from below. Fig. 2E is a top view of the light emitting device 100 shown in Fig. 2A, with the second mirror member 30b and the cover 50 omitted. Fig. 2F is a cross-sectional view of the light emitting device 100 shown in Fig. 2A, taken parallel to the YZ plane.

[0039] As will be described in detail later, in the light-emitting device 100 according to this embodiment, as shown in FIG. 2F , the laser light L emitted from the laser light source 20 is reflected by the first reflecting surface 30as and the second reflecting surface 30bs in this order. With this configuration, the traveling direction of the laser light L reflected by the first reflecting surface 30as and the second reflecting surface 30bs in this order can be directed in the +Z direction, regardless of whether the traveling direction of the laser light L emitted from the laser light source 20 deviates from the +Z direction, which is the design traveling direction. The first reflecting surface 30as reflects the laser light L emitted from the laser light source 20, changing the traveling direction of the laser light L in a direction away from the mounting surface 10us of the substrate 10. The second reflecting surface 30bs reflects the laser light L reflected by the first reflecting surface 30as, further changing the traveling direction of the laser light L in the +Z direction.

[0040] The position and orientation of the second mirror member 30b can be adjusted so that the laser light L reflected by the second reflecting surface 30bs travels in the +Z direction. By reflecting the laser light L reflected by the second reflecting surface 30bs on the reflecting surface 94s as shown in FIG. 1A , the traveling direction of the laser light L can be changed to the +X direction, which is the design traveling direction. As a result, multiple laser light beams L traveling in the +X direction can be effectively combined, and a high-power combined light can be output from the light-emitting module 200.

[0041] In a configuration in which the propagation direction of the laser light L incident on the reflecting surface 94s is not parallel to the designed +Z direction, the propagation direction of the laser light L reflected by the reflecting surface 94s deviates from the designed +X direction. Multiple laser light beams L with such a deviation in propagation direction may not be effectively combined, even if the deviation is only a few degrees, and the output of the combined light may decrease.

[0042] In contrast, in this embodiment, it is possible to reduce the deviation between the traveling direction of the laser light L reflected by the first reflecting surface 30as and the second reflecting surface 30bs in this order and the +Z direction, which is the designed traveling direction. As a result, it is possible to reduce the deviation between the traveling direction of the laser light L reflected by the reflecting surface 94s and the +X direction, which is the designed traveling direction. The angle formed between the traveling direction of the laser light L and the designed traveling direction is preferably, for example, 1° or less, and more preferably 0.1° or less. In this specification, the angle formed between the two directions has a positive value and does not have a negative value.

[0043] In this embodiment, the designed traveling direction of the laser light L reflected by the first reflecting surface 30as and the second reflecting surface 30bs in this order is parallel to the +Z direction, and the designed traveling direction of the laser light L reflected by the reflecting surface 94s is parallel to the +X direction, but the designed traveling directions are not limited to these directions.

[0044] In this specification, the direction in which the multiple first mounting surfaces 60s1 are arranged is referred to as the "first direction," and the traveling direction of the laser light L reflected by the first reflecting surface 30as and the second reflecting surface 30bs in this order is referred to as the "second direction." The reference plane Ref is parallel to the first direction. In this embodiment, the first direction is the +X direction, and the second direction is the +Z direction, but these directions are not limited to these. The second direction does not need to be perpendicular to the first direction as long as it intersects with the first direction.

[0045] The light emitting device 100 may be used for other purposes without being employed in the light emitting module 200 shown in FIGS. 1A and 1B.

[0046] Each component of the light emitting device 100 will be described below.

[0047] <Substrate 10> As shown in FIG. 2C , the substrate 10 has a mounting surface 10us and a lower surface 10Ls. The normal direction of the mounting surface 10us is the +Y direction. In this specification, the normal direction of a surface refers to the perpendicular direction to the surface, that is, the direction away from the object having the surface. In the example shown in FIG. 2C , the substrate 10 has a rectangular flat plate shape, but is not limited to this shape. The substrate 10 may have, for example, a polygonal, circular, or elliptical flat plate shape. The lower surface 10Ls of the substrate 10 is bonded to the first mounting surface 60s1 of the support base 60 via an inorganic bonding member such as a solder material.

[0048] The substrate 10 may be formed, for example, from a material having a thermal conductivity of 10 W / m·K or more and 2000 W / m·K or less. A substrate 10 having such high thermal conductivity can effectively transfer heat generated from the laser light source 20 during operation to the support base 60 shown in FIGS. 1A to 1C via the substrate 10. The substrate 10 may be formed, for example, from the same material as the support base 60. The dimension of the substrate 10 in the X direction may be, for example, from 1000 μm to 10,000 μm, the dimension in the Y direction may be, for example, from 100 μm to 5,000 μm, and the dimension in the Z direction may be, for example, from 1000 μm to 20,000 μm.

[0049] <Laser Light Source 20> As shown in FIG. 2C , the laser light source 20 is supported by the mounting surface 10us of the substrate 10. The laser light source 20 includes a submount 21, an edge-emitting semiconductor laser element 22 supported by the submount 21, a lens support member 23, and a fast-axis collimating lens 24. The semiconductor laser element 22 is supported by the mounting surface 10us of the substrate 10 via the submount 21. The semiconductor laser element 22 is disposed so as to emit laser light L toward the first reflecting surface 30as. The lens support member 23 has a shape that straddles the semiconductor laser element 22. The lens support member 23 supports the fast-axis collimating lens 24 by its end face. The components of the laser light source 20 may be treated as components of the light-emitting device 100.

[0050] The semiconductor laser element 22 emits laser light L from a rectangular end face. When the end face extends in the X direction and is a plane parallel to the XY plane, the laser light L emitted from the semiconductor laser element 22 in the +Z direction spreads relatively quickly in the YZ plane and spreads relatively slowly in the XZ plane. The fast axis direction of the laser light L is parallel to the Y direction, and the slow axis direction is parallel to the X direction.

[0051] The laser light source 20 emits laser light that is emitted from a semiconductor laser element 22 and transmitted through a fast axis collimating lens 24. The laser light L emitted from the laser light source 20 is collimated in the YZ plane, but is not collimated in the XZ plane. In this specification, "collimate" means not only making the laser light L parallel, but also reducing the divergence angle of the laser light L. A specific configuration of the laser light source 20 will be described later.

[0052] As shown in Fig. 2F, the semiconductor laser element 22 included in the laser light source 20 is sealed by the substrate 10, the frame 40, and the cover 50. This sealing is preferably airtight. The effect of airtight sealing increases as the wavelength of the laser light emitted from the semiconductor laser element 22 becomes shorter. This is because, in a configuration where the emission surface of the semiconductor laser element 22 is not airtight sealed and is exposed to the outside air, the shorter the wavelength of the laser light, the more likely it is that the emission surface will deteriorate during operation due to dust collection.

[0053] It should be noted that a surface-emitting semiconductor laser element such as a vertical-cavity surface-emitting laser (VCSEL) element may be used instead of the edge-emitting semiconductor laser element 22. The surface-emitting semiconductor laser element is arranged so that the laser light emitted from the semiconductor laser element travels in the +Z direction.

[0054] <First Mirror Member 30a and Second Mirror Member 30b> As shown in FIG. 2C , the first mirror member 30a is supported by the mounting surface 10us of the substrate 10. The first mirror member 30a has a uniform cross-sectional shape in the X direction. This cross-sectional shape is roughly triangular. The first mirror member 30a has a lower surface, a rear surface, and a slope connecting the lower surface and the rear surface. The lower surface is parallel to the XZ plane, and the rear surface is parallel to the XY plane. The normal direction of the slope is a direction parallel to the YZ plane, and forms an acute angle with the +Y direction and an acute angle with the -Z direction. The angle between the lower surface of the first mirror member 30a and the slope is 45°, but is not limited to this angle and may be, for example, between 30° and 60°.

[0055] The first mirror member 30a has a first reflecting surface 30as on the inclined surface. The first reflecting surface 30as is inclined with respect to the mounting surface 10us of the substrate 10 and faces diagonally upward. In this specification, diagonally upward means a direction that forms an angle of 30° to 60° with the +Y direction. As long as the first reflecting surface 30as can receive the laser light L emitted from the laser light source 20 and the normal direction of the first reflecting surface 30as is a direction that forms an angle of 30° to 60° with the +Y direction, the normal direction of the first reflecting surface 30as may or may not be parallel to the YZ plane.

[0056] 2F , the first reflecting surface 30as reflects the laser light L emitted from the laser light source 20 and changes the traveling direction of the laser light L in a direction away from the mounting surface 10us of the substrate 10. The angle between the direction in which the laser light L moves away from the mounting surface 10us of the substrate 10 and the normal direction of the mounting surface 10us can be, for example, between 0° and 5°. Because the angle has a tolerance of 5°, the position and orientation of the first mirror member 30a do not need to be adjusted as precisely as the position and orientation of the second mirror member 30b.

[0057] As shown in FIG. 2C , the second mirror member 30b is supported by the upper surface 50us of the cover 50. The second mirror member 30b has a uniform cross-sectional shape in the X direction. This cross-sectional shape is roughly trapezoidal. The second mirror member 30b has an upper surface, a lower surface, and a slope connecting the upper and lower surfaces. Each of the upper and lower surfaces is parallel to the XZ plane. The dimension of the lower surface in the X direction is equal to the dimension of the upper surface in the X direction. Meanwhile, the dimension of the lower surface in the Z direction is smaller than the dimension of the upper surface in the Z direction. The normal direction of the slope is parallel to the YZ plane and forms an acute angle with the −Y direction and an acute angle with the +Z direction. The angle between the upper surface of the second mirror member 30b and the slope is 45°, but is not limited to this angle and may be, for example, between 30° and 60°. The angle formed between the upper surface and the inclined surface of the second mirror member 30b may be equal to or different from the angle formed between the lower surface and the inclined surface of the first mirror member 30a.

[0058] The second mirror member 30b has a second reflecting surface 30bs on the inclined surface. At least a portion of the second reflecting surface 30bs is located above at least a portion of the first reflecting surface 30as. As shown in FIG. 2F , the second reflecting surface 30bs reflects the laser light L reflected by the first reflecting surface 30as, changing the traveling direction of the laser light L to the +Z direction.

[0059] As shown in FIG. 2F , a resin layer 32 is present between the lower surface of the second mirror member 30b and the upper surface 50us of the cover 50. The resin layer 32 is formed by curing the resin while the lower surface of the second mirror member 30b is in contact with the upper surface 50us of the cover 50 via the uncured resin. The resin may be, for example, a thermosetting resin that is cured by heating, or a photocurable resin that is cured by irradiation with ultraviolet or visible light. Before curing the resin, the following active alignment is performed. That is, with the laser light source 20 emitting laser light L, the position and orientation of the second mirror member 30b are appropriately adjusted so that the second reflecting surface 30bs changes the propagation direction of the laser light L in the +Z direction. This adjustment can be performed after the light-emitting device 100 is placed on the first mounting surface 60s1 of the support base 60 shown in FIGS. 1A to 1C , while the second mirror member 30b is held by a holding device.

[0060] The traveling direction of the laser light L can be adjusted by rotating the second mirror member 30b about the X-axis or Y-axis as a rotation axis to change its orientation. By rotating the second mirror member 30b about the X-axis as a rotation axis, the traveling direction of the laser light L can be changed up and down. By rotating the second mirror member 30b about the Y-axis as a rotation axis, the traveling direction of the laser light L can be changed left and right, with the traveling direction of the laser light L being the front direction.

[0061] Furthermore, by changing the position of the second mirror member 30b in the Z direction, the height of the optical axis of the laser light L can be adjusted. By shifting the second mirror member 30b along the +Z direction, the height of the optical axis of the laser light L can be reduced, and by shifting the second mirror member 30b along the -Z direction, the height of the optical axis of the laser light L can be increased. In this specification, the "optical axis of the laser light" refers to the axis that passes through the center of the far-field pattern of the laser light. The laser light traveling on the optical axis exhibits a peak intensity in the light intensity distribution of the far-field pattern.

[0062] Here, unlike the present embodiment, an example will be given in which the second mirror member 30b is fixed to the upper surface 50us of the cover 50 without adjusting its position or orientation. Even with such a configuration, by disposing a wedge between the second mirror member 30b and the slow-axis collimating lens 92 in the light-emitting module 200 shown in FIGS. 1A to 1C, the traveling direction of the laser light L reflected by the second reflecting surface 30bs can be directed in the +Z direction. The wedge has a light incident surface and a light reflecting surface located on opposite sides of each other. The normal direction of the light incident surface is parallel to the -Z direction, and the normal direction of the light exit surface is parallel to the YZ plane, forms an acute angle with the +Y direction or the -Y direction, and also forms an acute angle with the +Z direction. Due to refraction at the light incident surface and the light incident surface, which are not parallel to each other, the wedge can change the traveling direction of the laser light L passing through it. However, when using wedges, in order to direct the direction of travel of the laser light L in the +Z direction, it is necessary to prepare multiple wedges with different normal directions to the light emitting surface, and to select from the multiple wedges a wedge whose normal direction to the light emitting surface is in an appropriate direction.

[0063] In contrast to this, in this embodiment, by arranging the second mirror member 30b in an appropriate position and orientation, it is possible to direct the traveling direction of the laser light L reflected by the second reflecting surface 30bs in the +Z direction regardless of whether the traveling direction of the laser light L emitted from the laser light source 20 deviates from the +Z direction. In this embodiment, it is not necessary to prepare a plurality of second mirror members 30b having different angles formed between the top surface and the inclined surface and to select a second mirror member 30b with an appropriate angle from the plurality of second mirror members 30b.

[0064] The mirror members 30a and 30b shown in FIGS. 2B and 2C, the mirror member 94 shown in FIGS. 1A to 1C, and the mirror members 94a to 94c shown in FIG. 1D may each include, for example, a base having an inclined surface and a reflective surface formed separately on the inclined surface. The base may be formed of, for example, at least one material selected from the group consisting of glass, quartz, synthetic quartz, sapphire, ceramics, plastic, silicon, metal, silicone resin, and a dielectric material. The reflective surface may be formed of, for example, a reflective material such as a dielectric multilayer film or a metal material. This reflective surface corresponds to the first reflective surface 30as and the second reflective surface 30bs shown in FIG. 2B, the reflective surface 94s shown in FIG. 1A, and the reflective surfaces 94as to 94cs shown in FIG. 1D.

[0065] Alternatively, the first mirror member 30a, the second mirror member 30b, and the mirror members 94, 94a to 94c may each have a base with a slope, and the base may be made of the above-mentioned reflective material. In this case, the slope of the base corresponds to the first reflecting surface 30as, the second reflecting surface 30bs, and the reflecting surfaces 94s, 94as to 94cs.

[0066] <Frame 40> The frame 40 is positioned around the mounting surface 10us of the substrate 10 as shown in FIG. 2B and supports the cover 50 as shown in FIG. 2A. As shown in FIG. 2B, the frame 40 surrounds the laser light source 20 and the first mirror member 30a when viewed from the +Y direction, i.e., when viewed from above. As shown in FIG. 2C, the frame 40 has a protrusion 40p protruding inward from its inner surface. In the example shown in FIG. 2E, the protrusion 40p protrudes toward both side surfaces and the back surface of the submount 21. The protrusion 40p may also protrude toward the front surface of the submount 21. Alternatively, the protrusion 40p may protrude only from both side surfaces. The front surface of the submount 21 is located on the same side as the emission surface of the semiconductor laser element 22, and the back surface of the submount 21 is located on the opposite side from the emission surface of the semiconductor laser element 22. The side surfaces of the submount 21 connect the front and back surfaces of the submount 21.

[0067] As shown in Fig. 2C, the frame 40 has a first upper surface 40us1 and a second upper surface 40us2. The second upper surface 40us2 is the upper surface of the protrusion 40p, is located below the first upper surface 40us1, and is surrounded by the first upper surface 40us1 in a top view. As shown in Fig. 2E, the second upper surface 40us2 has a generally U-shape.

[0068] The first upper surface 40us1 is provided with a first bonding region 44a and an outer region 46 surrounding the first bonding region 44a. The first bonding region 44a and the outer region 46 each have a roughly rectangular annular shape. The first bonding region 44a improves bonding strength when bonding the cover 50 and the frame 40 via an inorganic bonding material such as solder. The outer region 46 prevents the inorganic bonding material bonding the cover 50 from flowing beyond the outer region 46. As shown in FIG. 2E , the first bonding region 44a and the outer region 46 surround the laser light source 20 and the first mirror member 30a in a top view. The first upper surface 40us1 is further provided with a first conductive region 42a and a second conductive region 42b that are electrically insulated from each other and located in the −Z direction from the first bonding region 44a and the outer region 46.

[0069] The second upper surface 40us2 is provided with a third conductive region 42c and a fourth conductive region 42d, which are electrically insulated from each other. The third conductive region 42c is electrically connected to the first conductive region 42a via internal wiring, and the fourth conductive region 42d is electrically connected to the second conductive region 42b via internal wiring. As shown in FIG. 2E, in a top view, the laser light source 20 and the first mirror member 30a are located between a portion of the third conductive region 42c extending in the Z direction and a portion of the fourth conductive region 42d extending in the Z direction. The third conductive region 42c is electrically connected to the semiconductor laser element 22 via the upper surface of the submount 21 and some of the wires 40w shown in FIG. 2B. The fourth conductive region 42d is electrically connected to the semiconductor laser element 22 via the remaining wires 40w shown in FIG. 2B. Therefore, power can be supplied to the laser light source 20 by applying a voltage between the first conductive region 42a and the second conductive region 42b.

[0070] As shown in FIG. 2D , the frame 40 further has a first lower surface 40Ls1 and a second lower surface 40Ls2. The second lower surface 40Ls2 partially comprises the lower surface of the protrusion 40p, is located higher than the first lower surface 40Ls1, and is surrounded by the first lower surface 40Ls1 when viewed from the -Y direction, i.e., from below. The second lower surface 40Ls2 has a roughly rectangular ring shape. Part or all of the substrate 10 shown in FIG. 2C is housed in a space surrounded by the step between the first lower surface 40Ls1 and the second lower surface 40Ls2. When viewed through the frame 40, the outer periphery of the second lower surface 40Ls2 surrounds the outer periphery of the mounting surface 10us of the substrate 10 when viewed from above, and the inner periphery of the second lower surface 40Ls2 is surrounded by the outer periphery of the mounting surface 10us of the substrate 10 when viewed from above.

[0071] A second bonding region 44b is provided over the entire first lower surface 40Ls1. The second bonding region 44b improves bonding strength when the support base 60 and the frame 40 shown in FIGS. 1A to 1C are bonded together via an inorganic bonding material such as a solder material. A third bonding region 44c is provided over the entire second lower surface 40Ls2. The third bonding region 44c is bonded to the peripheral region of the mounting surface 10us of the substrate 10 via an inorganic bonding material such as a brazing material. The third bonding region 44c improves bonding strength when the substrate 10 and the frame 40 are bonded together via an inorganic bonding material. The melting point of the brazing material is higher than the melting point of the solder material. Therefore, when the substrate 10 and the frame 40 are bonded together by heating the brazing material and then the solder material is heated to bond the substrate 10 and the laser light source 20, the possibility of the substrate 10 and the frame 40 becoming detached due to the heat applied to the solder material is reduced.

[0072] In the example shown in FIG. 2D , the second bonding region 44b is provided over the entire first lower surface 40Ls1, but the second bonding region 44b may be provided only in a portion of the first lower surface 40Ls1. Similarly, in the example shown in FIG. 2D , the third bonding region 44c is provided over the entire second lower surface 40Ls2, but the third bonding region 44c may be provided only in a portion of the second lower surface 40Ls2. Alternatively, the second bonding region 44b may not be provided on the first lower surface 40Ls1, or the third bonding region 44c may not be provided on the second lower surface 40Ls2. When the second bonding region 44b is not provided on the first lower surface 40Ls1, the frame 40 and the supporting base 60 are not bonded, and the substrate 10 and the supporting base 60 are bonded only at the lower surface 10Ls of the substrate 10.

[0073] 2F , the first lower surface 40Ls1 of the frame 40 is located on the same plane as the lower surface 10Ls of the substrate 10. The first lower surface 40Ls1 of the frame 40 may be located higher than the lower surface 10Ls of the substrate 10. Alternatively, the first lower surface 40Ls1 of the frame 40 may be located lower than the lower surface 10Ls of the substrate 10 as long as it does not interfere with bonding the substrate 10 and the supporting base 60 via the inorganic bonding member.

[0074] 1A and 1B, the frame 40 may be formed from the ceramic material described above. The frame 40 may have a dimension in the X direction of, for example, 3 mm or more and 15 mm or less, a maximum dimension in the Y direction of, for example, 1 mm or more and 5 mm or less, and a dimension in the Z direction of, for example, 3 mm or more and 30 mm or less.

[0075] The conductive regions 42a-42d, the bonding regions 44a-44c, and the outer region 46 may be formed from at least one metal material selected from the group consisting of Ag, Cu, W, Au, Ni, Pt, and Pd, for example. The conductive regions 42a-42d, the bonding region 44a, and the outer region 46 may be formed, for example, by providing a metal film on the entire upper surfaces 40us1 and 40us2 and patterning the metal film by etching.

[0076] <Cover 50> As shown in FIG. 2B , the cover 50 has an upper surface 50us and a lower surface 50Ls. The lower surface 50Ls of the cover 50 faces the mounting surface 10us of the substrate 10, and the upper surface 50us of the cover 50 is located opposite the lower surface 50Ls of the cover 50. In this specification, the lower surface 50Ls of the cover 50 is also referred to as the "facing surface." The cover 50 is located above the semiconductor laser element 22 and the first mirror member 30a. The cover 50 transmits the laser light L reflected by the first reflecting surface 30as.

[0077] The cover 50 has a light-shielding film 52 at least around a light-transmitting region 50t on the lower surface 50Ls that transmits the laser light L. In the example shown in Fig. 2C, the light-transmitting region 50t has a rectangular shape, but is not limited to this shape. The shape of the light-transmitting region 50t may be, for example, a circular shape or an elliptical shape.

[0078] Alternatively, the cover 50 may have the light-shielding film 52 on at least a portion of the periphery of the light-transmitting region 50t on the lower surface 50Ls. For example, when a portion of the edge of the light-transmitting region 50t coincides with a portion of the edge of the lower surface 50Ls, the light-shielding film 52 may be provided on at least a portion of the following region on the lower surface 50Ls. This region is a region on the lower surface 50Ls that is adjacent to the remaining portion of the edge of the light-transmitting region 50t other than the above-mentioned portion.

[0079] The light-shielding film 52 reduces the possibility that stray light other than the laser light L generated inside the light-emitting device 100 will leak to the outside of the light-emitting device 100. The light-shielding film 52 further reduces the possibility that ultraviolet light or visible light will reach the laser light source 20 when the resin layer 32 shown in FIG. 2F is formed by irradiation with ultraviolet light or visible light. The light-shielding film 52 also reduces the possibility that return light of the laser light L emitted to the outside of the light-emitting device 100 will reach the laser light source 20. If irradiation by ultraviolet light or visible light or return light can be reduced, the laser light source 20 will be less likely to be damaged.

[0080] 2C , the light-shielding film 52 is provided on the entire lower surface 50Ls except for the light-transmitting region 50t. The light-shielding film 52 thus provided further reduces the possibility that the stray light will leak to the outside of the light-emitting device 100 and that the ultraviolet light or visible light or the returned light will reach the laser light source 20.

[0081] Not only the light-transmitting region 50t but also the portion of the cover 50 that overlaps the light-transmitting region 50t in a top view transmits the laser light L. The portion of the cover 50 that transmits the laser light L may have a transmittance of, for example, 60% or more, and preferably 80% or more, for the laser light L. The remaining portion of the cover 50 may or may not have such light-transmitting properties.

[0082] 1A and 1B, the cover 50 may be formed from the aforementioned light-transmitting material. The cover 50 may have a dimension in the X direction of, for example, 3 mm or more and 15 mm or less, a dimension in the Y direction of, for example, 0.1 mm or more and 1.5 mm or less, and a dimension in the Z direction of, for example, 1 mm or more and 20 mm or less.

[0083] The light-shielding film 52 may be formed from the above-mentioned metal material, similar to the conductive regions 42a to 42d, the bonding regions 44a to 44c, and the outer region 46. The light-shielding film 52 may be formed, similar to the conductive regions 42a to 42d, the bonding region 44a, and the outer region 46, by providing a metal film on the entire lower surface 50Ls of the cover 50 and patterning the metal film by etching.

[0084] The peripheral region of the light-shielding film 52 is joined via an inorganic bonding material such as solder to the first bonding region 44a provided on the first upper surface 40us1 of the frame body 40. When the light-shielding film 52 is made of the above-mentioned metal material, the light-shielding film 52 improves the bonding strength when the cover 50 and the frame body 40 are joined via the inorganic bonding material.

[0085] 2A to 2C, the cover 50 has a flat plate shape, but is not limited to this shape. In a configuration in which the substrate 10 has a flat plate shape without the frame body 40, the cover 50 may have a box shape with an open bottom instead of a flat plate shape. The cover 50 having such a shape is supported by the mounting surface 10us of the substrate 10 and houses the laser light source 20 and the first mirror member 30a. Alternatively, the cover 50 having a box shape with an open bottom may be joined to the frame body 40, and the laser light source 20 and the first mirror member 30a may be surrounded by the cover 50 and the frame body 40.

[0086] As described above, this embodiment can realize the light emitting device 100 that can reduce the deviation between the traveling direction of the laser light L and the designed traveling direction. By employing such a light emitting device 100 in the light emitting module 200 shown in Figures 1A to 1C, the multiple laser beams L obtained by emitting the laser light L from each of the multiple light emitting devices 100 can be effectively combined and input to the optical fiber 80.

[0087] The light-emitting device 100 can be manufactured, for example, as follows. In the first step, the substrate 10, the laser light source 20, the first mirror member 30a, the second mirror member 30b, the frame 40, the plurality of wires 40w, and the cover 50 are prepared. In the next step, the frame 40 is bonded to the substrate 10. In the next step, the laser light source 20 and the first mirror member 30a are provided on the mounting surface 10us of the substrate 10. In the next step, the plurality of wires 40w for supplying power to the laser light source 20 are provided. In the next step, the cover 50 is bonded to the frame 40. In the next step, active alignment is performed with the lower surface of the second mirror member 30b in contact with the upper surface 50us of the cover 50 via uncured resin. In the next step, the resin is cured to form a resin layer 32 between the second mirror member 30b and the cover 50.

[0088] [DDL Device] Next, with reference to FIG. 3 , an example configuration of a DDL device according to an embodiment of the present disclosure will be described. FIG. 3 is a diagram schematically illustrating the configuration of a DDL device according to an exemplary embodiment of the present disclosure. The DDL device 1000 illustrated in FIG. 3 includes a plurality of light-emitting modules 200 according to this embodiment, a processing head 300, and an optical transmission fiber 250 that connects the light-emitting modules 200 to the processing head 300. In the example illustrated in FIG. 3 , the number of light-emitting modules 200 is four, but is not limited to this number. The number of light-emitting modules 200 may be one, two, three, or five or more.

[0089] The number of light-emitting devices 100 included in each light-emitting module 200 is determined according to the required optical output or irradiance. The wavelength of the laser light emitted from the light-emitting device 100 can also be selected according to the material to be processed. For example, when processing metals such as copper, brass, and aluminum, a semiconductor laser element with a central wavelength in the range of 350 nm to 550 nm can be suitably used. The wavelength of the laser light emitted from each light-emitting device 100 does not need to be the same; laser light with different central wavelengths can be superimposed. Furthermore, the effects of the present invention can be obtained even when using laser light with a central wavelength outside the range of 350 nm to 550 nm.

[0090] In the example shown in FIG. 3 , an optical fiber 80 extends from each of the multiple light-emitting modules 200. The resulting multiple optical fibers 80 are coupled to an optical transmission fiber 250 by an optical multiplexer 230. The optical multiplexer 230 may be, for example, a tapered fiber bundle (TFB). The processing head 300 focuses and irradiates the laser light emitted from the light-emitting end of the optical fiber 80 onto the target 400. In a case where one DDL device 1000 includes M light-emitting modules 200, each of which includes N light-emitting devices 100, and the optical output of each light-emitting device 100 is P watts, a laser beam with an optical output of up to P×N×M watts can be focused onto the target 400. Here, N is an integer greater than or equal to 2, and M is a positive integer. For example, if P = 20 watts, N = 22, and M = 12, an optical output of more than 5 kilowatts can be achieved.

[0091] [Configuration of laser light source 20] Next, an example of the configuration of the laser light source 20 shown in Fig. 2C will be described with reference to Fig. 4A and Fig. 4B. Fig. 4A is an exploded perspective view of the laser light source 20. Fig. 4B is a cross-sectional view of the laser light source 20 parallel to the YZ plane. Each component of the laser light source 20 will be described below.

[0092] As shown in FIG. 4A , the submount 21 has an upper surface 21us and a lower surface 21Ls that are parallel to the XZ plane. A metal film is provided on each of the upper surface 21us and the lower surface 21Ls. The metal film provided on the upper surface 21us improves the bonding strength when the semiconductor laser element 22 and the lens support member 23 are bonded to the submount 21 with an inorganic bonding material. The metal film provided on the upper surface 21us may also be used to supply power to the semiconductor laser element 22. The metal film provided on the lower surface 21Ls improves the bonding strength when the substrate 10 and the laser light source 20 shown in FIG. 2C are bonded via an inorganic bonding material. The metal films provided on each of the upper surface 21us and the lower surface 21Ls also help transfer heat generated by the semiconductor laser element 22 during operation to the substrate 10 via the submount 21. The submount 21 can be formed from, for example, the aforementioned ceramics, metal materials, or metal matrix composite materials, similar to the support base 60 shown in FIGS. 1A and 1B.

[0093] As shown in FIG. 4A , the semiconductor laser element 22 is supported by the upper surface 21us of the submount 21. The semiconductor laser element 22 has an emission surface 22e, one of two end surfaces intersecting the Z direction, and emits laser light in the +Z direction from the emission surface 22e. As the laser light travels in the +Z direction, it spreads at different speeds in the YZ plane and the XZ plane. The laser light spreads relatively quickly in the YZ plane and relatively slowly in the XZ plane. When not collimated, the spot of the laser light has an elliptical shape in the far field in the XY plane, with the major axis in the Y direction and the minor axis in the X direction.

[0094] The semiconductor laser element 22 can emit violet, blue, green, or red laser light in the visible region, or infrared or ultraviolet laser light in the invisible region. The peak emission wavelength of the violet light is preferably in the range of 400 nm to 420 nm, and more preferably in the range of 400 nm to 415 nm. The peak emission wavelength of the blue light is preferably in the range of more than 420 nm to 495 nm, and more preferably in the range of 440 nm to 475 nm. The peak emission wavelength of the green light is preferably in the range of more than 495 nm to 570 nm, and more preferably in the range of 510 nm to 550 nm. The peak emission wavelength of the red light is preferably in the range of 605 nm to 750 nm, and more preferably in the range of 610 nm to 700 nm.

[0095] The semiconductor laser element 22 emitting violet, blue, and green laser beams may be a laser diode containing a nitride semiconductor material, such as GaN, InGaN, or AlGaN. The semiconductor laser element 22 emitting red laser beams may be a laser diode containing an InAlGaP-based, GaInP-based, GaAs-based, or AlGaAs-based semiconductor material, for example.

[0096] As shown in FIG. 4A , the lens support member 23 is supported by the upper surface 21us of the submount 21. The lens support member 23 has two columnar portions 23a and a connecting portion 23b located between the two columnar portions 23a and connecting the two columnar portions 23a. The two columnar portions 23a are located on both sides of the semiconductor laser element 22, and the connecting portion 23b is located above the emission surface 22e of the semiconductor laser element 22. The lens support member 23 supports the fast axis collimating lens 24 by end faces 23as of the two columnar portions 23a. The lens support member 23 is located so as to straddle the semiconductor laser element 22 and does not prevent the laser light emitted from the semiconductor laser element 22 from entering the fast axis collimating lens 24.

[0097] The lens support member 23 may be formed, for example, from the ceramics described above, similar to the support base 60 shown in Figures 1A and 1B. The lens support member 23 may be formed, for example, from the optically transparent material described above, similar to the condenser lens 70 shown in Figures 1A and 1B. The lens support member 23 may be formed, for example, from at least one alloy selected from the group consisting of Kovar and CuW. The lens support member 23 may be formed, for example, from Si.

[0098] As shown in FIG. 4A , the fast axis collimating lens 24 may be, for example, a cylindrical lens having a uniform cross-sectional shape in the X direction. The fast axis collimating lens 24 has a flat surface on the light incident side and a convex curved surface on the light exit side. The convex curved surface has a curvature in the YZ plane. The focal point of the fast axis collimating lens 24 approximately coincides with the center of the light-emitting point on the exit surface 22 e of the semiconductor laser element 22. As shown in FIG. 4B , the fast axis collimating lens 24 collimates, in the YZ plane, the laser light emitted in the +Z direction from the exit surface 22 e of the semiconductor laser element 22. The region surrounded by the dashed line in FIG. 4B is where the intensity of the laser light is 1 / e of its peak intensity. ２ where e is the base of the natural logarithm. The fast axis collimating lens 24 may be formed from the aforementioned optically transparent material, for example, similar to the condenser lens 70 shown in FIGS. 1A and 1B.

[0099] 2F, the fast axis collimating lens 24 is located between the mounting surface 10us of the substrate 10 and the lower surface 50Ls of the cover 50, and is located on the optical path of the laser light L. Because the fast axis collimating lens 24 is disposed inside the sealed space formed by the substrate 10, the frame 40, and the cover 50, it can collimate the laser light L before it diverges significantly. This makes it possible to make the fast axis collimating lens 24 compact.

[0100] A collimating lens that collimates the laser light L emitted from the semiconductor laser element 22 not only in the YZ plane but also in the XZ plane may be used instead of the fast axis collimating lens 24. In that case, it is not necessary to provide the slow axis collimating lenses 92, 92a, and 92b in the light-emitting module 200 shown in Figures 1A to 1C and the light-emitting module 210 shown in Figure 1D.

[0101] The present disclosure includes light emitting devices described in the following items.

[0102] a plurality of light emitting devices, each comprising: a substrate having a mounting surface; a semiconductor laser element supported by the mounting surface; a first mirror member supported by the mounting surface; a cover having an opposing surface facing the mounting surface of the substrate and an upper surface located opposite to the opposing surface, the cover being positioned above the semiconductor laser element and the first mirror member; and a second mirror member supported by the upper surface of the cover; a plurality of third mirror members; and a condenser lens, wherein the first mirror member has a first reflecting surface, the first reflecting surface being inclined with respect to the mounting surface and facing obliquely upward; the second mirror member has a second reflecting surface, at least a portion of the second reflecting surface being located above at least a portion of the first reflecting surface; a light emitting module, wherein the first reflecting surface reflects the laser light and changes the direction of travel of the laser light in a direction away from the mounting surface of the board; the cover transmits the laser light reflected by the first reflecting surface; the second reflecting surface reflects the laser light reflected by the first reflecting surface and further changes the direction of travel of the laser light to a second direction intersecting the first direction; each of the plurality of third mirror members has a third reflecting surface, which reflects the laser light traveling in the second direction and changes the direction of travel of the laser light to the first direction; and the focusing lens couples a plurality of laser beams obtained by the laser light emitted from each of the plurality of light emitting devices being reflected by the third reflecting surface into an optical fiber.

[0103] [Item 2] The light-emitting module according to item 1, wherein a resin layer is present between the lower surface of the second mirror member and the upper surface of the cover.

[0104] [Item 3] The light-emitting module according to item 1 or 2, wherein the cover has a light-shielding film at least around a region of the facing surface of the cover through which the laser light passes.

[0105] [Item 4] The light emitting module according to any one of items 1 to 3, further comprising a fast axis collimating lens located between the mounting surface of the substrate and the opposing surface of the cover and on an optical path of the laser light.

[0106] [Item 5] The light-emitting module according to any one of items 1 to 4, wherein the substrate is formed from a material having a thermal conductivity of 10 W / m·K or more and 2000 W / m·K or less.

[0107] [Item 6] The light-emitting module according to any one of Items 1 to 5, further comprising a frame body positioned around the mounting surface of the substrate and supporting the cover, wherein the semiconductor laser element is hermetically sealed by the substrate, the frame body, and the cover.

[0108] The light emitting device of the present disclosure can be used to combine multiple laser beams to produce a high-power laser beam, and can be used in industrial fields where a high-power laser light source is required, such as cutting, drilling, local heat treatment, surface treatment, metal welding, and 3D printing of various materials.

[0109] 10: Substrate 10us: Mounting surface 10Ls: Bottom surface 20: Laser light source 21: Submount 21Ls: Bottom surface 21us: Top surface 22: Semiconductor laser element 22e: Emission surface 23: Lens support member 23a: Columnar portion 23as: End surface 23b: Connecting portion 24: Fast axis collimating lens 30a: First mirror member 30as: First reflecting surface 30b: Second mirror member 30bs: Second reflecting surface 32: Resin layer 40: Frame 40us1: First top surface 40us2: Second top surface 40Ls1: First bottom surface 40Ls2: Second bottom surface 40p: Protrusion 40w: Wire 42a: First conductive region 42b: Second conductive region 42c: Third conductive region 42d: Fourth conductive region 44a: First bonding region 44b: Second bonding region 44c: Third bonding region 46: Outer region 50: Cover 50us: Upper surface 50Ls: Lower surface 50t: Light-transmitting region 52: Light-shielding film 60, 62: Support base 60-1, 62-1: First portion 60-2, 62-2: Second portion 60-3, 62-3: Third portion 60s1: First mounting surface 60s2: Second mounting surface 60s3: Third mounting surface 70: Condenser lens 70a: Fast axis condenser lens 70b: Slow axis condenser lens 80: Optical fiber 80a: Light input end 80b: Light output end 82: Support member 92: Slow axis collimator lens 92a: Slow axis collimator lens 92b: slow axis collimator lens 94, 94a, 94b, 94c: mirror members 94s, 94as, 94bs, 94cs: reflecting surfaces 96: half-wave plate 98: polarizing beam splitter 100, 100-1, 100-2: light-emitting devices 200, 210: light-emitting modules 230: optical multiplexer 250: optical transmission fiber 300: processing head 400: object 1000: DDL device

Claims

1. A support base having a plurality of mounting surfaces aligned in a first direction; A plurality of light-emitting devices are disposed on each of the plurality of mounting surfaces, each of which includes: A substrate having a mounting surface; a semiconductor laser element supported by the mounting surface; a first mirror member supported by the mounting surface; a cover having an opposing surface facing the mounting surface of the substrate and an upper surface located on the opposite side to the opposing surface, the cover being located above the semiconductor laser element and the first mirror member; a second mirror member supported by the top surface of the cover; and A plurality of third mirror members; A focusing lens; Equipped with the first mirror member has a first reflecting surface, the first reflecting surface being inclined with respect to the mounting surface and facing obliquely upward; the second mirror member has a second reflecting surface, at least a portion of the second reflecting surface being located above at least a portion of the first reflecting surface; the semiconductor laser element is disposed so as to emit a laser beam toward the first reflecting surface, the first reflecting surface reflects the laser light to change a traveling direction of the laser light in a direction away from the mounting surface of the board; the cover transmits the laser light reflected by the first reflecting surface, the second reflecting surface reflects the laser light reflected by the first reflecting surface to further change the traveling direction of the laser light to a second direction intersecting the first direction, Each of the plurality of third mirror members has a third reflecting surface, and the third reflecting surface reflects the laser light traveling in the second direction to change the traveling direction of the laser light to the first direction, The condenser lens couples a plurality of laser beams obtained by the laser beams emitted from the plurality of light-emitting devices being reflected on the third reflecting surface into an optical fiber, the light-emitting module.

2. The light-emitting module according to claim 1 , wherein a resin layer is present between the lower surface of the second mirror member and the upper surface of the cover.

3. The light emitting module according to claim 1 , wherein the cover has a light blocking film at least around a region of the facing surface of the cover through which the laser light passes.

4. 3. The light emitting module according to claim 1, further comprising a fast axis collimating lens located between the mounting surface of the substrate and the opposing surface of the cover and on an optical path of the laser light.

5. 3. The light-emitting module according to claim 1, wherein the substrate is made of a material having a thermal conductivity of 10 W / m·K or more and 2000 W / m·K or less.

6. a frame body that is located around the mounting surface of the board and supports the cover, 3. The light emitting module according to claim 1, wherein said semiconductor laser element is hermetically sealed by said substrate, said frame, and said cover.